/******************************************************************************
 * Copyright (c) 2014, Hobu Inc. (howard@hobu.co)
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following
 * conditions are met:
 *
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 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided
 *       with the distribution.
 *     * Neither the name of the Howard Butler or Hobu, Inc.
 *       the names of its contributors may be
 *       used to endorse or promote products derived from this software
 *       without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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 ****************************************************************************/
#pragma once

#include <cmath>
#include <limits>

namespace hexer
{

// compares two values to within a given tolerance
// the value |tolerance| is compared to |actual - expected|
template<class T>
static bool compare_approx(const T& actual, const T& expected,
    const T& tolerance)
{
    const double diff = std::abs((double)actual - (double)expected);
    const double delta = std::abs((double)tolerance);

    if (diff > delta)
    {
        return false;
    }
    return true;
}

template<class T>
static bool compare_distance(const T& actual, const T& expected)
{
    const T epsilon = std::numeric_limits<T>::epsilon();
    return compare_approx<T>(actual, expected, epsilon);
}

} // namespace hexer

